More than one million people in the U.S. suffer from Type I diabetes, a disease in which pancreatic islets are no longer able to control glucose levels in the blood. The expectancy and quality of life of these patients is greatly compromised by diabetic complications that include retinopathies, renal failure, and vascular disease. An alternate therapeutic modality to regular insulin injections is transplantation of pancreatic islets from transgenic (allotransplantation) or nontransgenic (xenotransplantation) organisms. To suppress rejection by the recipient's immune system, transplanted islets are immunoisolated by enclosing them individually into microcapsules comprised of structurally stable, semipermeable membranes. The structural stability and selective permeability of the membrane ensures long-term viability and functionality of the islets.
Current methods for encapsulation generally include droplet generation, emulsion formation, polyelectrolyte multilayering, and direct polymerization from a surface-adsorbed initiator. Encapsulation methods are often restricted in terms of chemical composition, uniformity and thickness of the membrane, polymerization schemes, and applied stress to pancreatic islets. There is a need for an improved method for encapsulating islet cells.